1. Field of the Invention
The present invention is directed to a method, device, and system for transferring images to both sides of media cards or other products, and more particularly to a single-pass double-sided image transfer system that may find beneficial use in printing cards and other media.
2. Description of the Related Art
FIG. 1 depicts a long edge leading double-sided printer in accordance with the known prior art. The printer is structured to print rectangular media cards such as PVC media cards that are commonly known in the art. The phrase “long edge leading” refers to the primary orientation taken by media cards as they are manipulated through the printer during printing operations. In a long edge leading (“LEL”) orientation the long edges of the rectangular media card are oriented generally perpendicular to the media card's direction of movement. Alternatively, in a short edge leading orientation (“SEL”) the short edges of the rectangular media card are oriented generally perpendicular to the media card's direction of movement. The path of the media card through the printer depicted in FIG. 1 has been defined along X and Y axes for illustration purposes.
LEL card printers in general have the advantage, relative to their SEL counterparts, of faster printing. This is because it takes less time to transition from edge to edge LEL vs. SEL. However, LEL printers of the type illustrated in FIG. 1 have at least two undesirable design characteristics that result in relatively slow and inefficient printing or media card conversion operations. The first such characteristic is referred to herein as a paused LEL card encoding technique. The second such characteristic is referred to as a multi-pass double sided print operation. Each of these design characteristics are described below.
The depicted LEL double-sided printer 10 includes a card feeder 20 for storing a plurality of media cards 15, a flip station 25, an encoding station 30, a print station 35, and transfer station 40. During printing operations, a media card 15 is drawn from the card feeder 20 long edge first as shown. The media card 15 is drawn upwardly to the flip station 25 in a Y direction along arrow A. The flip station 25 rotates the media card 15 to proceed long edge leading in the X direction along arrow C to the encoding station 30. Conventional media cards (e.g., credit cards, etc.) include magnetic strips disposed longitudinally along one surface of the cards. The media card is positioned in the LEL orientation upon reaching the encoder and, thus, the media card's magnetic strip is positioned transverse to the media card's direction of movement. Accordingly, to allow for proper encoding the card is paused or held in place for a period of time at the encoding station to allow a transversely aligned magnetic read/write head to translate along the media card magnetic strip. This process is referred to above as the paused LEL card encoding technique.
If encoding processes are unsuccessful, the depicted printer 10 retracts the media card 15 from the encoding station 30 along arrow D to the flip station 25. The flip station 25 transmits the unsuccessfully encoded media card to a reject port 22 along arrow E as shown. If encoding processes are successful, the media card 15 is transmitted in the X direction along arrow F for multi-pass double-sided printing operations. The phrase “multi-pass double-sided printing” refers to printing operations that include distinct steps for printing to first and second surfaces of a media card. Such multi-pass double-sided printing operations are conventionally achieved by printing to a first side of the media card, inverting the media card, and printing to a second side of the media card with a single printing head as described further below.
The depicted printer 10 includes an intermediate thermal transfer media 43 disposed between an intermediate thermal transfer media supply roll 41 and an intermediate thermal transfer media take-up roll 42. The intermediate thermal transfer media supply roll 41 dispenses (in strip form) the intermediate thermal transfer media 43 past the print station 35 where print dye is applied to the intermediate thermal transfer media 43. Further downstream, the intermediate thermal transfer media 43 extends past the transfer station 40 where portions of the intermediate thermal transfer media 43 bearing print are transferred onto the media cards 15.
The depicted printer 10 also includes a color ribbon supply roll 36, a color ribbon take-up roll 37, and a ribbon printing head 38. The color ribbon supply roll 36 supplies a color ribbon 39 that has, for example, a sequence of colorant panels including yellow (Y), magenta (M), cyan (C) and/or black (K) panels for imprinting of a range of colors or light/dark shades onto the intermediate thermal transfer media 43. The color ribbon is routed so as to be coextensive to the intermediate thermal transfer media 43 between the ribbon printing head 38 and a platen 33. The ribbon printing head 38 is then thermally engaged to impart a printed image to a portion of the intermediate thermal transfer media 43.
The printed intermediate thermal transfer media 43 is routed downstream to the transfer station 40 as shown. The transfer station 40 is comprised of a heated roller 44 that is opposed by an idler roller 47. The media card 15 is coextensively aligned with a printed portion of the intermediate thermal transfer media 43 at the transfer station 40. The heated roller 44 engages the intermediate thermal transfer media 43 to impart a printed image to a first surface of the media card 15 in a first step of the multi-pass printing operation referenced above. The media card 15 is then transmitted back, along arrows G and D, to the flip station 25. The flip station 25 performs a second step of a multi-pass printing operation by inverting the media card 15. The media card 15 is then re-transmitted along arrows C and F to the transfer station 40 for completing a third-step of the multi-pass printing operation, namely, printing the second surface of the media card 15.
As referenced above, LEL printers of the type depicted in FIG. 1 contain paused LEL card encoding and multi-pass printing techniques that cause significant print and conversion inefficiencies. For example, by pausing the media card for a period of time to allow the transversely aligned read/write head to pass over the media card magnetic strip the depicted printer takes longer to perform encoding operations than standard SEL printers that use a stationary read/write head to encode the media card as the card is moved through the printer. Further, by shuttling the card back and forth in multiple passes to print to opposed surfaces of the media card the depicted printer takes longer than would be necessary if the printer were able to perform double-sided printing operations in a single-pass.
Therefore, it would be advantageous to provide an improved printer and printing process that does not require paused LEL card encoding and further is capable of transfer printing to opposed sides of a media card in a single pass without separate printing systems on opposite sides of the media card. It would be further desirable for such a printer and printing process to include an efficient card conversion architecture that reduces the need for complex shuttling of the media card within the printer.